campbell



3 Sheets-Sheet 1.

(No Model.)

H. CAMPBELL.

GAS ENGINE.

No. 367,184. Patented July 26, 1887.

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(No Model.) l 3 Sheets-Sheet 2.

H. CAMPBELL. GAS ENGINE.

N0.' 367,184. 1 Pateted July 26,1887.

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INVENTOR: WITNESSES'. mw @M11/06M,

(No Model.) a sheets-sheet 3.

E. CAMPBELL.

GAS ENGINE.

No. 367,184. Patented July 26, 1887.

UNITED STATES PATENT OFFICE.

HUGH CAMPBELL, OF ELLAND, COUNTY YORK, ENGLAND.

GASJ'ENGINE.

SPECIFICATION forming part of Letters Patent No. 367,184, dated July 26, 1887.

Application filed February 28, 1887. Serial N0.229,071. (No model.) Patented in England June 9, 1885, No. 6,990.

. gas-engines wherein in case the engine hasbut a single piston and cylinder an explosion will occur at every complete reciprocation of the Y piston; but in case there is a double piston and a compound cylinder there 4Will be two such explosions, whereby the working capacity of the engine will be increased.

The invention consists in the general construction of engines of this class, in mechanism for controlling the speed of the engine, and in mechanism for igniting the charge.

The invention is illustrated in the accompanying drawings, wherein Figure lis a sectional elevation, and Fig. 2 a sectional plan,of an engine wherein there is a double cylinder and a double piston working therein, ignition taking place at both ends of the cylinder. Fig. Sis a sectional elevation, and Fig. 4 a sectional plan, of an engine having two cylinders side by side, the pistons of which are both connected to the same crankshaft. Fig. 5 is a vertical cross-section of vthe engine shown in Figs. 3 and 4, through the exhaust-port, showing the mechanism for controllingthe exhaustvalve. Figs. 6and7 are detail views ofthe ignition mechanism. Fig. Sis

anend elevation, Fig. 9 a sectional elevation, Fig. 10 a sectional plan, and Fig. 11a cross section, (on a plane indicated by the line c b in Fig. 10,) of a gas-engine having a single cylinder. Figs. 12 and 13 are diagrams illusf trating the movements of the crank and piston, respectively, in an engine such as is shown in Figs. 8 to 11. Fig. 14E is a detailview on an enlarged scale of a modified meehanism for controlling the exhaust-Valve; and. Fig. 15. is a detail view on an enlarged scale ofl mechanism for controlling the inlet-valve.

Referring to Figs. 1 and 2, D E represent the two ends of along clyinder, in which is fitted a long trunk-piston, C. Said piston carries at its center a shaft, O', extending through slots C2 in the sides ofthe cylinder, the opposite ends of said shaft being connected by suitable rods to cranks B B on a drive-shaft, A. An igntion-chamber, d, is located at the end of each cylinder, each ignition-chamber being supplied with the combustible mixture through inlet check-valves .I J. The cylinder is provided with two exhaust-ports, FF, for

.each end, each exhaust-port being controlled by a check-valve, M. The exhaustport at each end is located at a distance from the end of the cylinder equal to one-half of thetravel of the piston.

The operation of the engine is as follows: Assume the piston to have just started toward the crank-shaft, impelled by the explosion of the gases at the .E end of the cylinder. The

movement of the piston in this direction filled with spent gases in the partfnearest the` piston and with fresh gas at the ignition end.

.On the return movement of the piston it compresses the gases, and so closes theinlet-valve J and opens the exhaust-valve M. Further movement of the piston expels the spent gases until the piston reaches and passes the exhaust-port F, when nothing remains in the E end of the cylinder except the fresh gas. This fresh c gas is then compressed by the piston until the piston reaches itslimit of movement in this direction, when the explosion again takes place, and the movements are repeated. In the meanwhile the same movements have taken place in the D end of the cylinder, and needno additional description. Thus in an engine thus constructed there will be two explosions at each rotation of the shaft A.

In Figs. 3 and4 is shown an engine wherein two single-acting cylinders are placed side by side, the two pistons B C of which are arranged to be connected to oppositely-located cranks B on the same shaft A. In this case ,the cycle of movements in each cylinder is exactly similar to that in either end of the cylinder shown in Figs. 1 and 2. The pistons in the two cylinders alternate in their move IOO ments, and there are two explosions at each rotation of the shaft A.

Themechanism for controlling the speed of the engine by regulating the valve M in the exhaust-port, and which is applicable to either form of engine described, is illustrated in Fig. 5. The valve M is provided with a valve-rod, c, which at its upper end outside of the valvecasing is connected to one end of a lever, b, [o pivoted to any suitable support. The opposite end of the lever is connected to a governor, L. When the speed ofthe engine exceeds the prescribed limit, the governor-balls will be lifted,rthus depressing the end of the lever b, x5 connected thereto,and liftingthe valve M from its seat. The exhaust-passage will thus be permanently open as long as'the speed is too great. IVhen the valve is open, fresh gas will no longer be introduced into the cylinder, since 2o the vacuum caused by the movement of the piston will be broken, and hence the inletvalve will not be opened to admit fresh gas. Therefore, no fresh gas being admitted, the speed of the engine willsoon be reduced,lowcr ing thegovernor-balls,and closing the valve M;

As soon as the valve is closed, the normal operation of the engine will be resumed.

The mechanism for igniting the combustt ble gases is shown in Figs. G and 7, wherein 3o is shown a bent pipe, K, which pipe is connected at its two ends to the ignition-chamber d of both cylinders when arranged side by side, as shown in Figs. 3 and 4. This pipe is so arranged that there is no through passage init, communication between the two ends being prevented by a stop-pieceor solid part, c, formed in the pipe.' This compound pipe is heated by a single light orjet, which keeps it at a red heat, so that when the combustible 4o mixture is alternately compressed into each branch of the pipe ignition will be produced in the cylinders at the proper time. In this manner only one light is required to cause the explosion in both cylinders.

4; In Figs. S to Il is shown a single-cylinderengine having but a single piston. The main shaft A has accordingly but a single crank, B. This engine is shown more completely than those previously described. Air is admitted 5o through a perforated plate, G, into a reservoir, H, and gas is admitted through the pipe I?. The gas and air are conveyed by inlet I, closed by inlet check-valve J, to the ignitionchamber (l. An ignition-pipe, K, similar to that shown in Figs. 6 and 7, but with only a single branch, connects with the ignitionchamber, and is heated by gas introduced through pipe e. The exhaust-port F is arranged at the side of the cylinder.

6o The action ofthe piston-of this engine is illustrated by the diagrams Figs. 12 and 13, Fig. 12 showing by the circlef'the different positions of the crank B and Fig. 13 the positions of the piston. When the crank is at points g and o5 j, the piston is atline g, and when the crank is at positions hand i the piston is at line handi. The action of the piston in reference to the gases is exactly the same as that described in connection with the engine shown in Figs. 1 and 2. One single-acting cylinder alone being shown, only one explosion occurs at each rotation of the shaft A.

As the exhaust-port in this engine is at the side, a slightly-modified form of controlling mechanism for the exhaust-valve is required, which is shown in detail in Fig. 14. The valve M in this case opens downward, being held to its seat by a spiral spring, Z, surrounding its stein m. The governor-balls in this case are arranged to lift the end'ofthe lever b,connected thereto,and so depress the valve, thereby opening the same when the speed ofthe engine rises above the normal.

In addition to controlling the speed by the exhaustvalve, there may be used in connection therewith mechanism for controlling the admission of the gas, so as to prevent possible waste of the same. This mechanism is illustrated in Figs. 8, 10, and l5. The gas-inlet pipe P is controlled by a valve, p, which is normally seated by a coiled spring, r, bearing against a collar, Q, carried by the valve-stein. In this case a similar governor, L, with lever b, is employed; but instead of the lever being connected to the valve-steni,there is suspended from it a rod, t, carrying at its lower end a tap-piece, s. The rod t hangs immediatelyin line with the valvestem. On the shaft A'isa cam, It, around which is a clip, as is usual in these cases, which clip is connected to a rod, S, which at every revolution of the cam strikes gently the tap-piece s, thereby forcing in the valve-stein and opening the valve to admit the gas. In ease, however, the speed of the engine becomes too great, the action of the governor lowers the rod 1, so that the tap-piece s is no longer struck by the rod S. The valve Pthus remains closed, shutting off the supply of gas until the lowered speed of the engine brings the tappiece again in line with the rod S.

I claim as my inventionl. In a gas-engine, a cylinder, a piston moving therein, and an ignition-chamber at one end of the cylinder, in combination with a gas and air inlet valve opening into said ignition-cham- ICO IIO

ber, which valve is opened by the vacuumV caused by the outward movement of the piston, an exhaust-port located in the cylinder'at a point midway of the movement of the piston, and a valve in the exhaust-passage, which is opened by the compression of the gases caused by the inward movement of the piston, subtially as set forth.

2. In a gas-engine, an elongated cylinder, a piston moving therein, and ignition-chambers at both ends of said cylinder, in combination with gas and air inlet valves opening into said ignitionchambers, which valves are opened by the vacuum caused by the movement of the piston away therefrom, exhaust-ports at each end of the cylinder, each located at a point midway of the movement of one end of the piston, and valves in the exhaustpassages which are opened by the compression of the gases caused by the movement of the piston toward the ignition ends of the cylinder, substantially as set forth, whereby when the piston is expelling the spent gases it is at the same time compressingl the fresh gases for a new eX- plosion. Y

3. In a gas-engine, a cylinder, a piston working therein, an 'ignition-chamber at one end of the cylinder, an air and gas inlet valve opening into the ignition-chamber, which is opened by the vacuum caused by the movement of the the vacuum caused by the outward movement of the piston, so that the inlet-valve will remain closed. 25

4. In a gasengine, two cylinders, ignitionchambers at the ends thereof, and pistons working in said cylinders which compress the fresh gases into said ignition-chambers, in combination with a bent tube or pipe opening at oppo- 3o site ends into said ignition-chambers, and a stop-piece in said pipe which closes communication between the two ignition-chambers, substantially as set, fort-h, whereby said bent pipe may be 'heated by a single jet and one-jet will 35 serve for the ignition of the gas in both cylinders.

In witness whereof I have hereunto signed my name in the presence of two subscribing witnesses.

HUGH CAMPBELL. IVitnesses:

HERRERI` INGHAM, ERNEST TURNER. 

